# @markuplint/ml-spec > Types and schema that specs of the Markup languages for markuplint Latest version **5.3.0** (published 2026-10-21) · MIT license · 0 weekly downloads ## Install ```sh npm install @markuplint/ml-spec pnpm add @markuplint/ml-spec yarn add @markuplint/ml-spec bun add @markuplint/ml-spec ``` ## Health **Score 65/100 (B)** — status: active. Positive: esm support; no vulnerabilities; has provenance; recently updated; high maintenance score. Warnings: low downloads; no types. ## Facts | | | |---|---| | Version | 5.3.0 | | Published | 2026-10-21 | | First published | 2019-03-28 | | Weekly downloads | 0 | | License | MIT | | TypeScript types | none | | Module format | ESM | | Node | >=24 | | Dependencies | 4 | | Unpacked size | 282.4 KB | | Known vulnerabilities | 0 | | Install scripts | no | | Provenance | attested (GitHub Actions) | | GitHub stars | 623 | | Author | Yusuke Hirao | | Maintainers | yusukehirao | ## Links - npm: https://www.npmjs.com/package/@markuplint/ml-spec - Repository: https://github.com/markuplint/markuplint - Homepage: https://github.com/markuplint/markuplint#readme - Issues: https://github.com/markuplint/markuplint/issues - npm.io page: https://npm.io/package/@markuplint/ml-spec ## Dependencies (4) - [type-fest](https://npm.io/package/type-fest.md) ^5.10.0 - [is-plain-object](https://npm.io/package/is-plain-object.md) ^5.1.0 - [@markuplint/types](https://npm.io/package/@markuplint/types.md) 5.3.0 - [@markuplint/ml-ast](https://npm.io/package/@markuplint/ml-ast.md) 5.3.0 ## Recent versions - 5.3.0 (latest) — 2026-10-21 - 5.0.0-rc.7 (rc) — 2026-08-31 - 5.0.0-rc.1 (next) — 2026-03-27 - 5.0.0-dev.5 (canary) — 2026-02-27 - 3.0.0-alpha.27 (dev) — 2022-12-20 - 5.2.0 — 2026-10-13 - 5.1.1 — 2026-10-09 - 5.1.0 — 2026-10-08 - 5.0.1 — 2026-09-22 - 5.0.0 — 2026-09-11 - 5.0.0-rc.6 — 2026-08-30 - 5.0.0-rc.5 — 2026-08-29 - 4.18.0 — 2026-04-22 - 5.0.0-rc.4 — 2026-04-19 - 5.0.0-rc.2 — 2026-04-15 - … 160 more at https://npm.io/package/@markuplint/ml-spec/versions ## README # @markuplint/ml-spec [![npm version](https://badge.fury.io/js/%40markuplint%2Fml-spec.svg)](https://www.npmjs.com/package/@markuplint/ml-spec) **Foundation package providing type definitions, W3C specification algorithms, and unified API for markup language specifications.** This package serves as the foundational layer for markuplint's specification system, providing: - **Type definitions** for markup language specifications (HTML, ARIA, SVG, MathML) - **W3C specification algorithms** (HTML Standard, WAI-ARIA 1.1/1.2/1.3 compliance) - **JSON schemas** that define the structure of element specifications - **Runtime utilities** for specification resolution, attribute validation, and content model checking - **Unified API** for consuming specification data from various sources The canonical HTML element specification data is provided by `@markuplint/html-spec`, which depends on this package for type definitions and algorithmic processing. ## Package Architecture This package serves as the foundation layer in markuplint's specification system: ``` @markuplint/ml-spec (Foundation Layer) ↓ provides types, algorithms, schemas @markuplint/html-spec (Data Layer) ↓ provides HTML specification data Framework-specific specs (Extension Layer) ↓ provide framework extensions Core packages (Application Layer) ↓ consume specifications for validation ``` ## Package Contents ### Type Definitions - **Core Types**: `ElementSpec`, `ExtendedSpec`, `MLMLSpec`, `ARIAVersion` - **ARIA Types**: Complete WAI-ARIA 1.1/1.2/1.3 type definitions - **Attribute Types**: HTML attribute definitions with validation rules - **Content Model Types**: Permitted content structure definitions Generated TypeScript types (do not edit directly): - `src/types/attributes.ts` - Attribute specification types - `src/types/aria.ts` - ARIA specification types - `src/types/permitted-structures.ts` - Content model types ### W3C Specification Algorithms **HTML Standard Algorithms**: - Focusable Area Algorithm (`src/algorithm/html/may-be-focusable.ts`) - Interactive Content classification - Content Model validation (`src/algorithm/html/get-content-model.ts`) **WAI-ARIA Specification Algorithms**: - **Accessible Name Computation** - W3C AccName 1.2 / HTML-AAM §4.1 compliant (`src/algorithm/aria/accname/`) - **Role Computation** - Explicit/implicit role resolution with conflict handling (`src/algorithm/aria/get-computed-role.ts`) - **Accessibility Tree Computation** - Element inclusion/exclusion logic (`src/algorithm/aria/is-exposed.ts`) - **ARIA Property Computation** - Attribute value resolution with HTML equivalents (`src/algorithm/aria/get-computed-aria-props.ts`) - **Required Context Validation** - Composite role validation (`src/algorithm/aria/has-required-owned-elements.ts`) **Specification Integration**: - Cross-specification utilities (`src/utils/get-spec-by-tag-name.ts`) - Version-aware specification resolution (`src/utils/resolve-version.ts`) - Schema-to-runtime conversion (`src/utils/schema-to-spec.ts`) ### JSON Schemas (Structure Definitions) - `schemas/element.schema.json` - Element specification schema - `schemas/aria.schema.json` - ARIA specification schema - `schemas/content-models.schema.json` - Content model schema - `schemas/global-attributes.schema.json` (generated) - Global attribute categories - `schemas/attributes.schema.json` (generated) - Attribute definition schema ### Schema Generators - `gen/gen.ts` - Builds generated schema files from data - `gen/global-attribute.data.*` - Source data for global attribute categories ### Runtime Utilities - **Spec Resolution**: `getSpecByTagName`, `getAttrSpecs`, `getRoleSpec` - **Content Model Utilities**: `getContentModel`, `isPalpableElements`, `isVoidElement` - **ARIA Utilities**: `getAria`, `getPermittedRoles`, `hasRequiredOwnedElements` - **Accessibility Utilities**: `getAccname`, `isExposed`, `mayBeFocusable` - **Schema Utilities**: `schemaToSpec`, `resolveNamespace`, `validateAriaVersion` - **Framework Extension**: Merges base HTML specs with framework-specific extensions **Note**: Attribute value types are defined in `@markuplint/types`. The schemas here reference `@markuplint/types/types.schema.json`. ## Relationship to @markuplint/html-spec **@markuplint/html-spec** provides the canonical HTML element specification data: - **Built output**: `index.json` (48K+ lines, consolidated specification data) - **Sources**: `src/spec-*.json` (individual element specifications) - **Build process**: `build.ts` → `generator/` scripts → enriched with MDN/W3C data **@markuplint/ml-spec** (this package) provides: - **Type definitions** that `@markuplint/html-spec` uses to structure its data - **JSON schemas** that validate the specification format - **Algorithms** that process and compute values from the specification data - **Runtime utilities** that consume the consolidated specification data This separation enables: - **Data updates** (`@markuplint/html-spec`) without affecting type definitions - **Algorithm improvements** (`@markuplint/ml-spec`) without regenerating data - **Framework extensions** that can reuse both type definitions and base HTML data ### Install `markuplint` already bundles this package. If you need to install it explicitly: ```bash npm install @markuplint/ml-spec # or yarn add @markuplint/ml-spec ``` ### Terminology - "HTML Schema" and "Specs" are used interchangeably in markuplint to mean the JSON Schema that describes HTML element specs (attributes, ARIA, content models, etc) and their TypeScript types. ### License MIT --- _Source: https://npm.io/package/@markuplint/ml-spec · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._